Since upgrading to Mavericks Onyx says my startup disk needs to be repaired

Since upgrading to Mavericks my iMac has become problematic. Little things like it becoming unresponsive for a couple of seconds while accessing the net or starting Excel.
I decided to run Onyx. It reports that my startup disk needs to be repaired.
I rebooted using Command & R and verified the disk. It reports that all is ok. Running Onyx again still reports "The volume needs to be repaired" I rebooted and ran the repair utility anyway, but it makes no difference to Onyx.
Can I assume my Onyx program is Duff?

Onyx is designed for a specific OS version. He hasn't released the Mavericks version yet to my knowledge. I'm surprised that whatever version you have runs. Wait til the official version for 10.9 is released.

Thanks for your prompt reply, very much appreciated.
I had visions of an impending hard drive failure.
So would I be better off just removing Onyx? as its now a defunct piece of software.

Not defunct, just not updated yet. He's working on it.
Titanium's Software • View topic - OnyX for Maverick